1. Field of the Invention
The present invention relates to an electronic control system for a vehicle seat that is convertible between different positions such as a seat position and a load floor position.
2. Background Art
A wide variety of vehicle seating arrangements are available for vans, minivans, and sport utility vehicles (“SUVs”). Vehicle seating systems may add versatility to vehicles that is derived from the ability to provide different seating configurations. Vehicle seating systems may include seats that are used in a conventional seating configuration or may be converted to provide a full or a partial load floor for hauling cargo. Some minivans are provided with removable seats that are releasably connected to anchoring devices secured to the vehicle compartment pan. More recently, seats are available that may fold into recesses in compartment pans to provide a continuous load floor without the need to remove the seats from the vehicle. Some seats are foldable into a console position with the seat back being folded forward over the seat base.
Most vehicle seating systems are manual and require a person to release a lever and reposition various portions of the seat to convert the seat to different modes. A recent innovation is the introduction of power folding seats such as that disclosed in U.S. Pat. No. 6,540,295 that is assigned to the assignee of this application. The power folding seat disclosed in this patent includes an electric motor that rotates the seat back between an upright, slanted seat back position and a generally horizontal load floor position. The motor used to fold the seat may be provided with a voltage regulator that monitors the voltage across the motor that may increase if a foreign object is encountered by the seat as it is moved by the motor. If a foreign object is contacted by the seat, the seat folding mechanism may attempt to continue the folding operation until the motor stalls. The motor stall condition is detected by the voltage regulator that interrupts operation of the motor. Folding a seat into a foreign object may damage the seat or the object.
The '295 patent also discloses the concept of operating the power folding seat upon receipt of an RF signal from an RF transmitter such as a key FOB. The '295 patent also discloses that location sensors may be provided upon various parts of the seat structure to be sure that the movable panels of the seat system are in the proper position for a given folding operation.
The seat system disclosed in the '295 patent is currently in production as the 2005 Cadillac SRX® sport utility vehicle. As currently produced, the seat has a manually actuated switch that must be held in to complete the folding operation. If the operator releases the switch during the folding operation, the seat folding operation is immediately interrupted to prevent damage to the seat folding mechanism or objects located on or around the seat. Some customers have indicated the desire to provide a power folding seat that does not require them to continuously hold the seat actuation button during the seat folding operation. Yet it is desirable to have an operator near a power folding seat as it folds to avoid problems that may be observed by a person as the seat is folded and unfolded. There is a need for a power seat folding system that does not require an operator to continuously hold a switch during an entire seat folding operation but will not operate unless the person is within close proximity to the vehicle during the folding operation.
Another problem associated with power seat folding mechanisms is that no feedback is typically provided to a user in the event the seat folding operation is unsuccessful. If, for example, the seat folding mechanism engages a foreign object and the motor stalls, the operator may not understand why the seat folding operation was interrupted. The operator also may not understand why the seat did not completely fold if the seat folding operation begins, but then terminates because the operator failed to continue to hold the button in during the entire folding operation. An operator may return the vehicle for service when no service is actually necessary if they do not understand why the seat folding operation was interrupted. There is a need for a power folding seat system that provides feedback to an operator in the event a seat folding operation is interrupted or to confirm that a seat has been moved to its fully folded or fully upright position for use as a seat.
These and other problems are addressed by Applicants'invention as summarized below.